Mayo Clinic researchers in collaboration with scientists at Perlegen Sciences, Inc. and funded by the Michael J. Fox Foundation for Parkinson's Research have produced the first large-scale whole genome map of genetic variability associated with Parkinson's disease.
Their results highlight changes in 12 genes that may increase the risk for Parkinson's disease in some people. Parkinson's disease is a disabling and currently incurable disease that affects millions of people worldwide.
The findings are reported in The American Journal of Human Genetics.
"This represents one of the first large-scale whole genome association studies of any disease," said the study's first author, Mayo Clinic neurologist Demetrius Maraganore, M.D. "It is something we've wanted to do for years, and now we finally had the technology and funding to make it happen. If confirmed, the findings may lead to new insights about the causes of Parkinson's disease."
Significance of the Findings
Both the findings and the technology that produced them are groundbreaking, representing one of the most comprehensive genetic studies of Parkinson's disease to date with nearly 200 million genetic tests (genotypes) completed. To accomplish this, researchers initially studied the association of about 200,000 single-letter variations in the genome known as single nucleotide polymorphisms, or "SNPs" (pronounced "snips") in patients with Parkinson's disease. The study examined DNA from 775 people with Parkinson's disease (cases) and from 775 people without Parkinson's disease (controls).
"To be most effective, a whole genome association study requires accurate testing of a large number of SNP markers that are distributed across the human genome in a dense and informative pattern," says Dr. Maraganore. "In this respect, our collaborators at Perlegen have set a new standard."
"In one year, the Michael J. Fox Foundation and Mayo Clinic have generated results that will greatly focus future research efforts in Parkinson's disease," explained David Cox, M.D., Ph.D., chief scientific officer of Perlegen Sciences. "If replication of only one of these findings leads to a better understanding of the causes of the disease or improvements in the early detection or treatment of patients, we will have made significant progress."
Noteworthy findings include: